Information to change the world | |
Find Topics, Titles, Names related to your query |
|
The Moonlit Stream
For relief from the stresses and strains of life, there is nothing like spending a few hours sitting beside a flowing river. A river, unlike a lake, moves. It is going somewhere. It’s like life passing you by, and for a change it’s rather nice to just sit there and let it. Of course, if you want a placid experience, it’s better to sit beside a river that is deep and slow-moving, usually an “older river”, or one just before it enters a lake or the ocean. Here it has already been through the rough plunges, twists, turns and rapids of its youth, further up in the higher land where it had its beginning. For a river, in general terms, begins life slowly, with the trickle of brooks and streams, becomes strong and energetic further down, and becomes placid when reaching the bottom lands and deltas at the end of its existence. A river in its upper reaches tends to be fast flowing, how fast depending on how steep the land is. Thus it has more power to erode through the silt and sand to the rock below, carrying stones and even small boulders along with it. This is the “collecting” phase, when it picks up and sweeps along everything in its path. As it moves along, it also dissolves minerals in the rocks, and tumbles rocks and stones together, making them smooth and round. In an old stream bed, you won’t find a lot of rough edges and sharp crevices. However, because of the cutting action of the fast water, the stream bed will be V-shaped and the banks steep. It is at this stage that waterfalls are formed. Since some rock is hard and some is soft, the soft rock gets worn away more quickly. Where a band of hard rock crosses the river, a pool will form, until the water cascades over the hard rock to the softer rock below, eroding it further. Gradually the force of the water over the fall erodes the rock at the bottom of it, undermining the harder rock above and causing the waterfall to retreat upstream, creating a steep gorge downstream. As the fast, explosive young river reaches more gently sloping lands, the river slows down. No longer strong enough to pick up particles, it now begins to deposit what it has collected upstream. Since its cutting and eroding powers are reduced, it starts to meander, turning this way and that, depending on the lay of the land. However, it still has some power to erode. The current along the outer bank of a curving river will flow more quickly than along the inner bank, carving away at the outer and depositing sediment on the inner, thus increasing the curve of a river. The banks of the rivers are now commonly muddy. Water loving plants and trees such as cedars and willows, able to withstand the occasional flood, will line its banks and the atmosphere will be lush, deep and quiet. As the river enters the lake or sea, the sediments collected upstream will be dropped, often choking the mouth of the river with mud flats over which the flowing water must flow to reach the lake. The build-up of sediments creates deltas which can be so broad and flat, and so intersected by a bewildering number of branched and separate streams, that it is sometimes hard to find your way through them to the open water beyond. One trick to aid the lost boater, is to watch the weeds at the bottom of the river bed and go wherever they point, since no matter how slow the current, the river vegetation will bend with it. If there are no weeds, try stirring up a little of the sediment and watching which way it settles. Rivers have always had a great many uses for mankind, from travel corridors to power generators. Modern man has also made great use of them as handy and continuous flush toilets for all the garbage and wastes it produces. Nothing like dumping your chemicals into the river and watching the waters just sweep them away – out of sight, out of mind. Unfortunately, rivers are also the collectors of nature’s most precious and easily destroyed resource – fresh water – the stuff that every creature, man or animal, depends on to survive. Our bodies are, after all, 99% water. It is time we treated our rivers with the reverence they deserve. Subject headings Lakes & Rivers – Nature – Rivers – Saugeen River |
Connect with Connexions |